Polycondensation catalyst for producing polyester and production of polyester using the same

Patent metadata

Field	Value
Publication number	US-2021170371-A1
Application number	US-201816769313-A
Country	US
Kind code	A1
Filing date	Dec 11, 2018
Priority date	Dec 22, 2017
Publication date	Jun 10, 2021
Grant date	—

Abstract

The invention provides a polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction of a dicarboxylic acid or an ester-forming derivative thereof and a glycol, wherein the polycondensation catalyst comprises particles of a water-insoluble or hardly water-soluble phosphate having on the surfaces a coating layer of titanic acid in an amount, of 0.1 to 100 parts by weight in terms of TiO2 per 100 parts by weight of the phosphate.

First claim

1 . A polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction of a dicarboxylic acid or an ester-forming derivative thereof and a glycol, wherein the polycondensation catalyst comprises particles of a water-insoluble or hardly water-soluble phosphate having on the surfaces a coating layer of titanic acid in an amount of 0.1 to 100 parts by weight in terms of TiO 2 per 100 parts by weight of the phosphate.

2 . The polycondensation catalyst according to claim 1 , wherein the phosphate is an orthophosphate, a metaphosphate, a pyrophosphate, a phosphate glass, a phosphite or a hypophosphite.

3 . The polycondensation catalyst according to claim 1 , wherein the counter ion of the phosphate anion is at least one cation of a metal selected from the group consisting of alkaline earth metals, aluminum, titanium, zirconium, and zinc.

4 . The polycondensation catalyst according to claim 3 , wherein the alkaline earth metal is calcium or magnesium.

5 . The polycondensation catalyst according to claim 1 , wherein the phosphate is dibasic calcium phosphate, tribasic calcium phosphate, calcium pyrophosphate, calcium dihydrogenpyrophosphate, magnesium pyrophosphate or magnesium metaphosphate.

6 . The polycondensation catalyst according to claim 1 , wherein the particles of the phosphate have on the surfaces a coating layer formed of titanic acid in an amount of 1 to 50 parts by weight in terms of TiO 2 per 100 parts by weight of phosphate.

7 . A polyester comprising the polycondensation catalyst according to claim 1 .

8 . The polyester comprising the polycondensation catalyst according to claim 7 , wherein the content of the polycondensation catalyst is in the range of 1 to 40 ppm in terms of titanium atom based on the weight of the polyester to be obtained.

9 . A method for producing polyester, comprising subjecting a dicarboxylic acid or an ester-forming derivative thereof and a glycol to polycondensation by an esterification reaction or a transesterification reaction in the presence of the polycondensation catalyst according to claim 1 .

10 . A method for producing polyester comprising preparing oligomers containing a bis(hydroxyalkyl) ester of an aromatic dicarboxylic acid by an esterification reaction or a transesterification reaction of the aromatic dicarboxylic acid or an ester-forming derivative thereof and an alkylene glycol, and then subjecting the oligomers to melt-polycondensation in the presence of the polycondensation catalyst according to claim 1 .

11 . A method for producing polyester comprising subjecting a dicarboxylic acid or an ester-forming derivative thereof and a glycol to polycondensation by an esterification reaction or a transesterification reaction in the presence of the polycondensation catalyst according to claim 1 , wherein the polycondensation catalyst is present in an amount of 1 to 40 ppm in terms of titanium atom based on the weight of the polyester to be obtained.

12 . A method for producing polyester comprising preparing oligomers containing a bis(hydroxyalkyl) ester of an aromatic dicarboxylic acid by an esterification reaction or a transesterification reaction of the aromatic dicarboxylic acid or an ester-forming derivative thereof and an alkylene glycol, and then subjecting the oligomers to melt-polycondensation in the presence of the polycondensation catalyst according to claim 1 , wherein the polycondensation catalyst is present in an amount of 1 to 40 ppm in terms of titanium atom based on the weight of the polyester to be obtained.

13 . A method for producing a polycondensation catalyst for producing polyester, comprising:
while maintaining a water slurry containing water-insoluble or hardly water-soluble particles of a phosphate at a temperature in the range of 5 to 100° C., adding to the water slurry a titanium compound in an amount of 0.1 to 100 parts by weight in terms of TiO 2 relative to 100 parts by weight of the phosphate, and adding an alkali to the resulting mixture to hydrolyze the titanium compound at a pH in the range of 3 to 12 to form a coating layer of titanic acid on the surfaces of the particles of the phosphate; drying and disintegrating the particles of the phosphate having the coating layer on the surfaces.

Assignees

• Sakai Chemical Industry Co

Inventors

• SOGA Yuhei
• Kamon Akihiro

Classifications

• C08K3/24

  Acids; Salts thereof {(C08K3/16 takes precedence)} · CPC title

• C08G63/183

  Terephthalic acids · CPC title

• C08K2003/326

  Magnesium phosphate · CPC title

• C08K2003/321

  Phosphates · CPC title

• C08K2003/325

  Calcium, strontium or barium phosphate · CPC title